Int J Prosthodont 32 (2019), No. 5 9. Sep. 2019
Int J Prosthodont 32 (2019), No. 5 (09.09.2019)
Page 439-443, doi:10.11607/ijp.6262, PubMed:31486816
Strength and Adaptation of Stereolithography-Fabricated Zirconia Dental Crowns: An In Vitro Study
Li, Rong / Wang, Yong / Hu, Menglong / Wang, Yungan / Xv, Yongxiang / Liu, Yushu / Sun, Yuchun
Purpose: To evaluate the physical and mechanical properties of zirconia ceramic manufactured with stereolithography and to quantitatively analyze the internal and marginal adaptation of the zirconia ceramic dental crowns.
Materials and Methods: A resin-based zirconia suspension with a solid content of 45 vol% was prepared. Zirconia dental crowns (n = 5) for the maxillary right first molar were designed and manufactured. Physical and mechanical properties-including density, sintering shrinkage, flexural strength, Weibull parameters, phase composition, and microstructure-of the stereolithography-manufactured zirconia crowns were evaluated. A three-dimensional subtractive analysis technique was used to evaluate the internal and marginal adaptation.
Results: The stereolithography-manufactured zirconia (n = 22) achieved a flexural strength of 812 ± 128 MPa and a Weibull modulus of 7.44. Quantitative analysis of the fabricated zirconia crowns showed a cement space of 63.40 ± 6.54 μm in the occlusal area, 135.08 ± 10.55 μm in the axial area, and 169.58 ± 18.13 μm in the marginal area.
Conclusion: Within the limits of this study, the strength of the stereolithography-manufactured zirconia was adequate for fabricating dental crowns. However, internal and marginal adaptation are not yet ideal for clinical application.